BacCeh is a legendary Runeword created by combining a Bac Rune of Ritual and a Ceh Rune of Invocation.
How to Create BacCeh
You can create BacCeh by adding the legendary Bac Rune of Ritual and the magic Ceh Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Bac - Travel 5 meters. (50)
Ceh - Summon a Spirit Wolf to attack enemies for 8 seconds. (100)
Overflow
BacCeh can not overflow because the amount of Offering you receive from the Bac Rune exactly fills the required Offering of the Ceh Rune.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.